Computer and other electronic devices generally require a medium in which digital data can be stored and retrieved. Data storage devices come in a variety of forms and serve a variety of purposes. These devices can be broken down into two general categories: solid state and non-solid state storage devices.
Non-solid state devices are devices that contain moving parts. Some typical non-solid state storage devices are hard disc drives, CD/RW drives and discs, DVD/R/RW drives and discs, floppy discs, tape drives and probe memory devices. These storage devices move one or more media surfaces and/or the associated data head relative to one another to position the data head relative to a desired location or area on the media. The data is then written to or read from this data location. In disc drives for example, data is stored on a disc that rotates at an essentially constant velocity. By moving the head over the rotating disc, all memory locations or sectors of the disc can be accessed.
Solid state memory devices differ from non-solid state devices in that they typically have no moving parts. One example of solid state memory is flash memory, such as used in a Compact Flash Memory Card. Flash memory is used primarily for easy and fast information storage in such devices as digital cameras, home video game consoles and personal digital assistants.
Flash memory has typically been the storage media of choice for consumers using small electronic devices that require memory storage. Removable solid state storage devices are becoming increasingly popular. Smart Media and Compact Flash are both well known, especially as “electronic film” for digital cameras or as memory cards in personal digital assistants. The advantage of flash memory in these devices is that they are noiseless, have generally faster access than a typical hard drive, and they are generally smaller and lighter. Further, the power consumption of a flash memory device is typically lower than that of a hard disc drive. However, flash memory is relatively expensive when compared to hard disc drives for an equivalent memory size. Further, a hard disc drives typically have much greater storage capacities than a flash memory device or other solid state memory devices.
Manufacturers of non-solid state memory devices are attempting to create solutions for these small electronic devices requiring data storage. Numerous attempts have been made to provide the users with the benefits of both a flash memory and a hard disc in a single non-solid state storage device. One attempt has been to remove the write caching feature found in a hard disc drive and write data directly from the drive to the disc. However, this approach has been quite problematic in that it has caused an increase in power consumption and a reduction in the efficiency of the drive.
Embodiments of the present disclosure provide solutions to these and other problems, and offer other advantages over the prior art.